A network model for initial stage sintering

Densification of powders by initial stage sintering has been investigated through computer simulations. In the simulations, every particle center is represented by a node and every contact between neighboring particles by a discrete element. The velocity of each node is related to applied and sintering forces arising from the deformation mechanisms which are physically active. These processes are controlled by grain boundary and surface diffusion and determine the constitutive laws for the behavior of each discrete element. The contribution of each discrete element is then assembled into a system of equations that represent the behavior of the powder system network. Solution of these equations provides predictions of the motion of particles during sintering. The results are used to characterize the free sintering of metal powders as well as stress assisted sintering. (C) 1998 Elsevier Science Ltd.